This invention relates generally to the field of devices which are used to impart an external annular or radial bead or shoulder to a hollow tube or pipe. More particularly, the invention relates to such devices utilizing a clamp to secure the tube, a beading die having an axial guide pin or mandrel surrounded by an annular tube receiving channel and means to mount the die onto a ram, whereby the die can be pressed against the end of the tube to force the tube against the clamp to produce the bead.
In many applications where gas or fluids need to be conducted through a tube, a fitting known as a bead/O-ring connection is used to seal the joint or connection between the tube and the component to which it attaches Such fittings are common in hydraulic, pneumatic and liquid systems. The normal production cycle in the industry is for the original equipment manufacturer (OEM), such as General Motors, Ford, Caterpillar to have the beaded fluid line assembly fabricated by a specialty fabrication vendor which specializes in the high speed high volume production of "blue-printed" fluid line assemblies that have the bead/O-ring seal configuration. Typical methodology for producing a beaded tube utilizes either a two-step procedure using one die to reduce the tube diameter and a second die to form the bead, or the use of rotary forming equipment. The beaded tube may be connected to the system several different ways, typically utilizing a mated male nut and female nut combination with the O-ring sealing any gap between the bead and one of the nuts. When the systems fail and a beaded tube connection needs to be replaced, it is usually necessary to obtain a replacement OEM tube. This often results in considerable delay before the equipment can be used again. The concept behind this invention is to provide a means for the duplication of traditional, highly specialized, high production, normally non-duplicatable, procedures at the after-market or repair shop level with inexpensive tooling that simplifies the process.
It is an object of this invention to provide an apparatus which enables formation of a beaded replacement tube of proper size from standard tube stock, obviating the need to locate an OEM replacement part. It is a further object to provide such an apparatus which utilizes a clamp to grasp the tube and provide a deformation backstop, a beading die having an axial mandrel which corresponds to the internal diameter of the tube being shaped and an annular receiving channel to receive the end of the tube, and a powered ram to advance a beading die against the tube and backstop to cold press the tube to form the radial bead in a single operation step.